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Dominick, Marine Mechanic
Category: Boat
Satisfied Customers: 1009
Experience:  25 Years Experience as Mechanic, 20 Yrs Boat Yard Owner/Mechanic, Factory Certified
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Hallo and from Germany. My brother and me have a Mercury

Customer Question

Hallo and good morning from Germany.
My brother and me have a Mercury Black Max 2.0 V6 150hp from 1985. Serial no. 0A138857. We have had much trouble with this engine, but still now we were able to solve all issues by ourself. But now we are helpless. Maybe you can help us.
After we have changed different parts and the machine works fine we started to review all settings. And now it becomes to be a little bit strange, because the ignition time seems to be not ok. That means the timing light (Equus 590-518) shows a marking at 10°, but however not BTDC, but ATDC(!). If we try now to adjust the timing toward BTDC the machine starts to splutter. Also the adjusting range of the lever at the trigger has been reached.
So, what happens?
- Flange of center hub at cankshaft in right position
- Flywheel adjusted on center hub to requirements (TDC 1st cyl and marking are ok)
Submitted: 1 year ago.
Category: Boat
Expert:  Jeff G. replied 1 year ago.

Did you move the center hub of the flywheel? The center hub is not designed to be moved.

How are you determining TDC?

What rpm are you turning to check rpm?

I'm not familiar with that timing light, Does it have a spark advance capability? We've found many of the timing lights simply don't work well on 2 stroke outboards.